Folding knife



FIG. 1 is a left side elevational view of a folding knife, the opposite side being a mirror image thereof, showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a rear elevational view thereof;

FIG. 6 is a left side elevational view thereof, showing the blade in a folded configuration;

FIG. 7 is a top perspective view thereof; and,

FIG. 8 is a bottom perspective view thereof.

The dashed lines throughout the figures represent a perimeter of a knife blade and form no part of the claimed invention. 

CLAIM The ornamental design for a folding knife, as shown and described. 